Noun: (1)a military vehicle(LAV) used for the express purpose of nasturbation typically found in deployed settings to boost the morale of male soldiers, never cleaned...think about it....possesses distinct functified smell

" Pollie Bear is the quickest person in the Spank Tank."

"Fernie never goes to the Spank Tank he only uses his wack shack, he's high class."

"The Spank Tank is for public use, but a wack shack is for private enjoyment."